Hair conditioning shampoo compositions are provided which contain a combination of conditioning agents including emulsified silicones, cationic polymers and certain fatty acid polyesters of polyols. Suitable fatty acid polyesters are sucrose pentalaurate, sucrose tetraoleate, sucrose pentaerucate, sucrose tetraerucate, sucrose tetrastearate, sucrose pentaoleate, sucrose octaoleate, sucrose pentatallowate, sucrose trirapeate, sucrose tetrarapeate, sucrose pentarapeate, sucrose tristearate and sucrose pentastearate, and mixtures thereof. The compositions give improved hair conditioning benefits, especially to hair which has been damaged, e.g. through environmental exposure or harsh mechanical or chemical treatments such as heat styling, perming or bleaching.

This invention relates to hair conditioning shampoo compositions containing a combination of conditioning agents including emulsified silicones, cationic polymers and certain fatty acid polyesters of polyols.
The use of conditioning agents in hair shampoo formulations is well known and widely documented. A variety of conditioning agents have been described in this context, the principal classes of such agents being silicones, cationic polymers and oily materials such as hydrocarbons, higher alcohols, fatty acid esters, glycerides and fatty acids.
Fatty acid polyesters of cyclic polyols and/or sugar derivatives have been described as a component of hair conditioning formulations in the following documents:
WO98/04241 discloses that a conditioning system comprising a mixture of polyol carboxylic acid ester and particular nonionic water-soluble polymers is valuable in shampoo compositions for the delivery of improved hair feel and manageability. Cationic cellulose derivative polymer materials may be included in the compositions as optional ingredients.
WO96/37594 discloses a mild, foam producing personal cleansing composition with good skin feel attributes which is based on a combination of an oil dispersing nonionic surfactant and dispersed oil phase which is a mixture of a liquid polyol fatty acid polyester and the second oil component comprising one or more non-polar oils preferably selected from mineral oil, petrolatum, water-insoluble silicones, soya bean oils and mixtures thereof. The use of this mixed oil system is said to deliver improved skin feel.
WO98/04240 describes a shampoo composition containing a particular surfactant base of short chain alkyl sulphate and alkyl ethoxy sulphate in combination with a conditioning system comprising an insoluble oil conditioning agent selected from silicone materials, liquid polyol carboxylic acid esters and mixtures thereof.
JP-A-10/077,215 describes a cosmetic material consisting of saccharide fatty acid ester and one or more siloxanes selected from methyl polysiloxane, methyl phenyl siloxane and methyl polycyclosiloxane. The composition is said to provide good combing and feel after washing when used as a hair rinse or treatment.
A problem encountered with conditioning shampoo formulations is that the conditioning performance may be insufficient for many people, particularly in regions such as Japan and South East Asia where consumers desire a high level of conditioning and a xe2x80x9cweightyxe2x80x9d feel to their hair. Simply raising the level of conditioning agent in the formulation is not a satisfactory solution, since some conditioning agents tend to build up on the hair and be difficult to rinse off at high levels, leading to an undesirably slimy or coated feel.
To enhance conditioning efficacy, various combinations of conditioning ingredients in shampoo formulations have been proposed as follows:
Cationic polymers have been described for the enhancement of the deposition of silicone from a cleansing shampoo base in EP 0 432 951 and EP 0 529 883.
WO 93/08787 describes a tri-component conditioning system for delivery from shampoo composed of insoluble silicone, cationic polymer of specified charge density and an oily liquid for providing shine and lustre to the hair which is preferably selected from, inter alia, hydrocarbon oils such as paraffin oil and mineral oil, and alkyl/alkenyl esters of fatty acids such as isopropyl isostearate and isocetyl stearoyl stearate.
The present inventors have found that a specific combination of conditioning agents: emulsified silicones, cationic polymers and fatty acid polyesters of cyclic polyols and/or sugar derivatives, gives surprisingly improved overall conditioning compared to the various binary combinations of those individual ingredients which are disclosed in the prior art.
Furthermore, hair softness is particularly improved.
The compositions of the invention also have particular utility in the treatment of hair which has been damaged, e.g. through environmental exposure or harsh mechanical or chemical treatments such as heat styling, perming or bleaching. In such cases, the benefits of softness and ease of combing provided by compositions of the present invention are especially apparent.
The present invention provides an aqueous shampoo composition comprising, in addition to water:
i) at least one cleansing surfactant chosen from anionic, zwitterionic and amphoteric surfactants or mixtures thereof, and
ii) a combination of conditioning agents including:
(a) emulsified particles of an insoluble silicone;
(b) a cationic polymer, and
(c) a fatty acid polyester of a polyol selected from cyclic polyols, sugar derivatives and mixtures thereof.
Shampoo compositions according to the invention will comprise one or more cleansing surfactants which are cosmetically acceptable and suitable for topical application to the hair. Further surfactants may be present as an additional ingredient if sufficient for cleansing purposes is not provided as emulsifying agent for the oily or hydrophobic components (such as silicones) present in the shampoo.
It is preferred that shampoo compositions of the invention comprise at least one further surfactant (in addition to that used as emulsifying agent) to provide a cleansing benefit.
Suitable cleansing surfactants, which may be used singularly or in combination, are selected from anionic, amphoteric and zwitterionic surfactants, cationic surfactants, and mixtures thereof. The cleansing surfactant may be the same surfactant as the emulsifier, or may be different. Preferred cleansing surfactants are selected from anionic, amphoteric and zwitterionic surfactants, and mixtures thereof.
Examples of anionic surfactants are the alkyl sulphates, alkyl ether sulphates, alkaryl sulphonates, alkanoyl isethionates, alkyl succinates, alkyl sulphosuccinates, N-alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates, alkyl ether carboxylates, and alpha-olefin sulphonates, especially their sodium, magnesium, ammonium and mono-, di- and triethanolamine salts. The alkyl and acyl groups generally contain from 8 to 18 carbon atoms and may be unsaturated. The alkyl ether sulphates, alkyl ether phosphates and alkyl ether carboxylates may contain from 1 to 10 ethylene oxide or propylene oxide units per molecule.
Typical anionic surfactants for use in shampoos of the invention include sodium oleyl succinate, ammonium lauryl sulphosuccinate, ammonium lauryl sulphate, sodium dodecylbenzene sulphonate, triethanolamine dodecylbenzene sulphonate, sodium cocoyl isethionate, sodium lauryl isethionate and sodium N-lauryl sarcosinate. The most preferred anionic surfactants are sodium lauryl sulphate, triethanolamine monolauryl phosphate, sodium lauryl ether sulphate 1 EO, 2EO and 3EO, ammonium lauryl sulphate and ammonium lauryl ether sulphate 1EO, 2EO and 3EO.
Examples of amphoteric and zwitterionic surfactants include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines (sultaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphopropionates, alkylamphoglycinates, alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates, wherein the alkyl and acyl groups have from 8 to 19 carbon atoms. Typical amphoteric and zwitterionic surfactants for use in shampoos of the invention include lauryl amine oxide, cocodimethyl sulphopropyl betaine and preferably lauryl betaine, cocamidopropyl betaine and sodium cocamphopropionate.
The shampoo composition can also include co-surfactants, to help impart aesthetic, physical or cleansing properties to the composition. A preferred example is a nonionic surfactant, which can be included in an amount ranging from 0% to about 5% by weight based on total weight.
For example, representative nonionic surfactants that can be included in shampoo compositions of the invention include condensation products of aliphatic (C8-C18) primary or secondary linear or branched chain alcohols or phenols with alkylene oxides, usually ethylene oxide and generally having from 6 to 30 ethylene oxide groups.
Other representative nonionics include mono- or di-alkyl alkanolamides. Examples include coco mono- or di-ethanolamide and coco mono-isopropanolamide.
Further nonionic surfactants which can be included in shampoo compositions of the invention are the alkyl polyglycosides (APGs). Typically, the APG is one which comprises an alkyl group connected (optionally via a bridging group) to a block of one or more glycosyl groups. Preferred APGs are defined by the following formula:
ROxe2x80x94(G)n
wherein R is a branched or straight chain alkyl group which may be saturated or unsaturated and G is a saccharide group.
R may represent a mean alkyl chain length of from about C5 to about C20. Preferably R represents a mean alkyd chain length of from about C8 to about C12. Most preferably the value of R lies between about 9.5 and about 10.5. G may be selected from C5 or C6 monosaccharide residues, and is preferably a glucoside. G may be selected from the group comprising glucose, xylose, lactose, fructose, mannose and derivatives thereof. Preferably G is glucose.
The degree of polymerisation, n, may have a value of from about 1 to about 10 or more. Preferably, the value of n lies in the range of from about 1.1 to about 2. Most preferably the value of n lies in the range of from about 1.3 to about 1.5.
Suitable alkyl polyglycosides for use in the invention are commercially available and include for example those materials identified as: Oramix NS10 ex Seppic; Plantaren 1200 and Plantaren 2000 ex Henkel.
The total amount of surfactant (including any co-surfactant, and/or any emulsifying agent) in shampoo compositions of the invention is generally from 0.1 to 50% by weight, preferably from 5 to 30%, more preferably from 10% to 25% by weight of the total shampoo composition.
The silicone is insoluble in the aqueous matrix of the shampoo composition of the invention and so is present in an emulsified form, with the silicone present as dispersed particles.
Suitable silicones include polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone.
Also suitable for use in compositions of the invention are hydroxyl functional silicones, in particular polydimethyl siloxanes having hydroxyl end groups which have the CTFA designation dimethiconol.
Also suitable for use in compositions of the invention are silicone gums having a slight degree of cross-linking, as are described for example in WO 96/31188. These materials can impart body, volume and stylability to hair, as well as good wet and dry conditioning.
A further preferred class of silicones for inclusion in shampoos of the invention are amino functional silicones. By xe2x80x9camino functional siliconexe2x80x9d is meant a silicone containing at least one primary, secondary or tertiary amine group, or a quaternary ammonium group.
Examples of suitable amino functional silicones include:
(i) polysiloxanes having the CTFA designation xe2x80x9camodimethiconexe2x80x9d, and the general formula:
HOxe2x80x94[Si(CH3)2xe2x80x94Oxe2x80x94]xxe2x80x94[Si(OH)(CH2CH2CH2xe2x80x94NHxe2x80x94CH2CH2NH2)xe2x80x94Oxe2x80x94]yxe2x80x94H
xe2x80x83in which x and y are numbers depending on the molecular weight of the polymer, generally such that the molecular weight is between about 5,000 and 500,000.
(ii) polysiloxanes having the general formula:
Rxe2x80x2aG3-axe2x80x94Si(OSiG2)nxe2x80x94(OSiGbRxe2x80x22-b)mxe2x80x94Oxe2x80x94SiG3-axe2x80x94Rxe2x80x2a
xe2x80x83in which:
G is selected from H, phenyl, OH or C1-8 alkyl, e.g. methyl;
a is 0 or an integer from 1 to 3, preferably 0;
b is 0 or 1, preferably 1;
m and n are numbers such that (m+n) can range from 1 to 2000, preferably from 50 to 150;
m is a number from 1 to 2000, preferably from 1 to 10;
n is a number from 0 to 1999, preferably from 49 to 149, and
Rxe2x80x2 is a monovalent radical of formula xe2x80x94CqH2qL in which q is a number from 2 to 8 and L is an aminofunctional group selected from the following:
xe2x80x94NRxe2x80x3xe2x80x94CH2xe2x80x94CH2xe2x80x94N(Rxe2x80x3)2
xe2x80x94N(Rxe2x80x3)2
xe2x80x94N+(Rxe2x80x3)3Axe2x88x92
xe2x80x94N+H(Rxe2x80x3)2Axe2x88x92
xe2x80x94Nxe2x80x94H2(Rxe2x80x3)Axe2x88x92
xe2x80x94N(Rxe2x80x3)xe2x80x94CH2xe2x80x94CH2xe2x80x94N+H2(Rxe2x80x3)Axe2x88x92
in which Rxe2x80x3 is selected from H, phenyl, benzyl, or a saturated monovalent hydrocarbon radical, e.g. C1-20 alkyl, and;
A is a halide ion, e.g. chloride or bromide.
Suitable amino functional silicones corresponding to the above formula include those polysiloxanes termed xe2x80x9ctrimethylsilylamodimethiconexe2x80x9d as depicted below, and which are sufficiently water insoluble so as to be useful in compositions of the invention:
Si(CH3)3xe2x80x94Oxe2x80x94[Si(CH3)2xe2x80x94Oxe2x80x94]xxe2x80x94[Si(CH3)(Rxe2x80x94NHxe2x80x94CH2CH2NH2)xe2x80x94Oxe2x80x94]yxe2x80x94Si(CH3)3
wherein x+y is a number from about 50 to about 500, and wherein R is an alkylene group having from 2 to 5 carbon atoms. Preferably, the number x+y is in the range of from about 100 to about 300.
(iii) quaternary silicone polymers having the general formula:
{(R1)(R2)(R3)N+CH2CH(OH)CH2O(CH2)3[Si(R4) (R5)xe2x80x94Oxe2x80x94]nxe2x80x94Si(R6)(R7)xe2x80x94(CH2)3xe2x80x94Oxe2x80x94CH2CH(OH)CH2N+(R8)(R9)(R10)}(Xxe2x88x921)2
xe2x80x83wherein R1 and R10 may be the same or different and may be independently selected from H, saturated or unsaturated long or short chain alk(en)yl, branched chain alk(en)yl and C5-C8 cyclic ring systems;
R2 thru"" R9 may be the same or different and may be independently selected from H, straight or branched chain lower alk(en)yl, and C5-C8 cyclic ring systems;
n is a number within the range of about 60 to about 120, preferably about 80, and
Xxe2x88x92 is preferably acetate, but may instead be for example halide, organic carboxylate, organic sulphonate or the like.
Suitable quaternary silicone polymers of this class are described in EP-A-0 530 974.
Amino functional silicones suitable for use in shampoos of the invention will typically have a mole % amine functionality in the range of from about 0.1 to about 8.0 mole %, preferably from about 0.1 to about 5.0 mole %, most preferably from about 0.1 to about 2.0 mole %. In general the amine concentration should not exceed about 8.0 mole % since we have found that too high an amine concentration can be detrimental to total silicone deposition and therefore conditioning performance.
Specific examples of amino functional silicones suitable for use in the invention are the aminosilicone oils DC2-8220, DC2-8166, DC2-8466, and DC2-8950-114 (all ex Dow Corning), and GE 1149-75, (ex General Electric Silicones).
An example of a quaternary silicone polymer useful in the present invention is the material K3474, ex Goldschmidt.
In general, the conditioning performance of the emulsified silicone in the shampoo composition of the invention tends to increase with increased viscosity of the silicone itself (not the emulsion or the final shampoo composition).
For dimethicone and dimethiconol-type silicones, the viscosity of the silicone itself is typically at least 10,000 cst, preferably at least 60,000 cst, most preferably at least 500,000 cst, ideally at least 1,000,000 cst. Preferably the viscosity does not exceed 109 cst for ease of formulation. For amino functional-type silicones, the viscosity of the silicone itself is not particularly critical and can suitably range from about 100 to about 500,000 cst.
Emulsified silicones for use in hair shampoos of the invention will typically have an average silicone particle size in the composition of less than 30, preferably less than 20, more preferably less than 10 microns. In general, reducing the silicone particle size tends to improve conditioning performance. Most preferably the average silicone particle size of the emulsified silicone in the composition is less than 2 microns, ideally it ranges from 0.01 to 1 micron. Silicone emulsions having an average silicone particle size of  less than 0.15 microns are generally termed microemulsions.
Particle size may be measured by means of a laser light scattering technique, using a 2600D Particle Sizer from Malvern Instruments.
Suitable silicone emulsions for use in the invention are also commercially available in a pre-emulsified form.
Examples of suitable pre-formed emulsions include emulsions DC2-1766, DC2-1784, and microemulsions DC2-1865 and DC2-1870, all available from Dow Corning. These are all emulsions/microemulsions of dimethiconol. Cross-linked silicone gums are also available in a pre-emulsified form, which is advantageous for ease of formulation. A preferred example is the material available from Dow Corning as DC X2-1787, which is an emulsion of cross-linked dimethiconol gum. A further preferred example is the material available from Dow Corning as DC X2-1391, which is a microemulsion of cross-linked dimethiconol gum.
Pre-formed emulsions of amino functional silicone are also available from suppliers of silicone oils such as Dow Corning and General Electric. Particularly suitable are emulsions of amino functional silicone oils with non ionic and/or cationic surfactant. Specific examples include DC929 Cationic Emulsion, DC939 Cationic Emulsion, DC949 Cationic emulsion, and the non-ionic emulsions DC2-7224, DC2-8467, DC2-8177 and DC2-8154 (all ex Dow Corning).
Mixtures of any of the above types of silicone may also be used. Particularly preferred are hydroxyl functional silicones, amino functional silicones and mixtures thereof.
The total amount of silicone incorporated into compositions of the invention depends on the level of conditioning desired and the material used. A preferred amount is from 0.01 to about 10% by weight of the total composition although these limits are not absolute. The lower limit is determined by the minimum level to achieve conditioning and the upper limit by the maximum level to avoid making the hair and/or skin unacceptably greasy.
When the silicone is incorporated as a pre-formed emulsion as described above, the exact quantity of emulsion will of course depend on the concentration of the emulsion, and should be selected to give the desired quantity of silicone in the final composition.
A cationic polymer is an essential ingredient in shampoo compositions of the invention, for enhancing conditioning performance of the shampoo.
The cationic polymer may be a homopolymer or be formed from two or more types of monomers. The molecular weight of the polymer will generally be between 5 000 and 10 000 000, typically at least 10 000 and preferably in the range 100 000 to about 2 000 000. The polymer will have cationic nitrogen containing groups such as quaternary ammonium or protonated amino groups, or a mixture thereof.
The cationic nitrogen-containing group will generally be present as a substituent on a fraction of the total monomer units of the cationic polymer. Thus when the polymer is not a homopolymer it can contain spacer non-cationic monomer units. Such polymers are described in the CTFA Cosmetic Ingredient Directory, 3rd edition. The ratio of the cationic to non-cationic monomer units is selected to give a polymer having a cationic charge density in the required range.
Suitable cationic polymers include, for example, copolymers of vinyl monomers having cationic amine or quaternary ammonium functionalities with water soluble spacer monomers such as (meth)acrylamide, alkyl and dialkyl (meth)acrylamides, alkyl (meth)acrylate, vinyl caprolactone and vinyl pyrrolidine. The alkyl and dialkyl substituted monomers preferably have C1-C7 alkyl groups, more preferably C1-3 alkyl groups. Other suitable spacers include vinyl esters, vinyl alcohol, maleic anhydride, propylene glycol and ethylene glycol.
The cationic amines can be primary, secondary or tertiary amines, depending upon the particular species and the pH of the composition. In general secondary and tertiary amines, especially tertiary, are preferred.
Amine substituted vinyl monomers and amines can be polymerized in the amine form and then converted to ammonium by quaternization.
The cationic polymers can comprise mixtures of monomer units derived from amine- and/or quaternary ammonium-substituted monomer and/or compatible spacer monomers.
Suitable cationic polymers include, for example:
copolymers of 1-vinyl-2-pyrrolidine and 1-vinyl-3-methyl-imidazolium salt (e.g. chloride salt), referred to in the industry by the Cosmetic, Toiletry, and Fragrance Association, (CTFA) as Polyquaternium-16. This material is commercially available from BASF Wyandotte Corp. (Parsippany, N.J., USA) under the LUVIQUAT tradename (e.g. LUVIQUAT FC 370);
copolymers of 1-vinyl-2-pyrrolidine and dimethylaminoethyl methacrylate, referred to in the industry (CTFA) as Polyquaternium-11. This material is available commercially from Gaf Corporation (Wayne, N.J., USA) under the GAFQUAT tradename (e.g., GAFQUAT 755N);
cationic diallyl quaternary ammonium-containing polymers including, for example, dimethyldiallyammonium chloride homopolymer and copolymers of acrylamide and dimethyldiallylammonium chloride, referred to in the industry (CTFA) as Polyquaternium 6 and Polyquaternium 7, respectively;
mineral acid salts of amino-alkyl esters of homo- and co-polymers of unsaturated carboxylic acids having from 3 to 5 carbon atoms, (as described in U.S. Pat. No. 4,009,256);
cationic polyacrylamides(as described in WO95/22311).
Other cationic polymers that can be used include cationic polysaccharide polymers, such as cationic cellulose derivatives, cationic starch derivatives, and cationic guar gum derivatives.
Cationic polysaccharide polymers suitable for use In compositions of the invention include those of the formula:
Axe2x80x94Oxe2x80x94[Rxe2x80x94N+(R1)(R2)(R3)Xxe2x88x92],
wherein: A is an anhydroglucose residual group, such as a starch or cellulose anhydroglucose residual. R is an alkylene, oxyalkylene, polyoxyalkylene, or hydroxyalkylene group, or combination thereof. R1, R2 and R3 independently represent alkyl, aryl, alkylaryl, arylalkyl, alkoxyalkyl, or alkoxyaryl groups, each group containing up to about 18 carbon atoms. The total number of carbon atoms for each cationic moiety (i.e., the sum of carbon atoms in R1, R2 and R3) is preferably about 20 or less, and X is an anionic counterion.
Cationic cellulose is available from Amerchol Corp. (Edison, N.J., USA) in their Polymer JR (trade mark) and LR (trade mark) series of polymers, as salts of hydroxyethyl cellulose reacted with trimethyl ammonium substituted epoxide, referred to in the industry (CTFA) as Polyquaternium 10. Another type of cationic cellulose includes the polymeric quaternary ammonium salts of hydroxyethyl cellulose reacted with lauryl dimethyl ammonium-substituted epoxide, referred to in the industry (CTFA) as Polyquaternium 24. These materials are available from Amerchol Corp. (Edison, N.J., USA) under the tradename Polymer LM-200.
Other suitable cationic polysaccharide polymers include quaternary nitrogen-containing cellulose ethers (e.g. as described in U.S. Pat. No. 3,962,418), and copolymers of etherified cellulose and starch (e.g. as described in U.S. Pat. No. 3,958,581).
A particularly suitable type of cationic polysaccharide polymer that can be used is a cationic guar gum derivative, such as guar hydroxypropyltrimonium chloride (Commercially available from Rhone-Poulenc in their JAGUAR trademark series).
Examples are JAGUAR C13S, which has a low degree of substitution of the cationic groups and high viscosity. JAGUAR C15, having a moderate degree of substitution and a low viscosity, JAGUAR C17, having a high degree of substitution and a high viscosity, JAGUAR C16, which is a hydroxypropylated cationic guar derivative containing a low level of substituent groups as well as cationic quaternary ammonium groups, and JAGUAR 162 which is a high transparency, medium viscosity guar having a low degree of substitution.
Preferably the cationic polymer is selected from cationic cellulose and cationic guar gum derivatives.
A further essential component in shampoo compositions of the invention is a fatty acid polyester of a polyol selected from cyclic polyols, sugar derivatives and mixtures thereof.
By xe2x80x9cpolyolxe2x80x9d is meant a material having at least four hydroxyl groups. The polyols used to prepare the fatty acid polyester will preferably have from 4 to 12, more preferably from 4 to 11, most preferably from 4 to 8 hydroxyl groups.
By xe2x80x9cfatty acid polyesterxe2x80x9d is meant a material in which at least two of the ester groups are independently of one another attached to a fatty (C8 to C22 alkyl or alkenyl) chain. For a given material, prefixes such as xe2x80x9ctetra-xe2x80x9d, xe2x80x9cpenta-xe2x80x9d indicate the average degrees of esterification. The compounds exist as a mixture of materials ranging from the monoester to the fully esterified ester.
Cyclic polyols are the preferred polyols used to prepare the fatty acid polyester in the present invention. Examples include inositol, and all forms of saccharides. Saccharides, in particular monosaccharides and disaccharides, are especially preferred.
Examples of monosaccharides include xylose, arabinose, galactose, fructose, sorbose and glucose. Glucose is especially preferred.
Examples of disaccharides include maltose, lactose, cellobiose and sucrose. Sucrose is especially preferred.
Examples of suitable sugar derivatives include sugar alcohols, such as xylitol, erythritol, maltitol and sorbitol, and sugar ethers such as sorbitan.
The fatty acids used to prepare the fatty acid polyester in the present invention have from 8 to 22 carbon atoms. They can be branched or linear, and saturated or unsaturated.
Examples of suitable fatty acids include caprylic, capric, lauric, myristic, myristoleic, palmitic, palmitoleic, stearic, 12-hydroxystearic, oleic, ricinoleic, linoleic, linolenic, arachidic, arachidonic, behenic, and erucic acids. Erucic acid is particularly preferred.
Mixed fatty acid moieties from source oils which contain substantial amounts of the desired unsaturated or saturated acids can be used as the acid moieties to prepare fatty acid polyesters suitable for use in the hair treatment composition of the invention. The mixed fatty acids from the oils should contain at least 30%, preferably at least 50% of the desired unsaturated acids. For example, high erucic rapeseed oil fatty acids can be used instead of pure C20-C22 unsaturated acids, and hardened, i.e. hydrogenated, high erucic rapeseed oil fatty acids can be used instead of pure C20-C22 saturated acids. Preferably the C20 and higher acids, or their derivatives, e.g. methyl or other lower alkyl esters, are concentrated, for example by distillation. The fatty acids from palm kernel oil or coconut oil can be used as a source of C8 to C12 acids, and those from cotton seed oil and soya bean oil as a source of C16 to C18 acids.
Specific examples of suitable fatty acid polyesters are sucrose pentalaurate, sucrose tetraoleate, sucrose pentaerucate, sucrose tetraerucate, sucrose tetrastearate, sucrose pentaoleate, sucrose octaoleate, sucrose pentatallowate, sucrose trirapeate, sucrose tetrarapeate, sucrose pentarapeate, sucrose tristearate and sucrose pentastearate, and mixtures thereof. Sucrose pentaerucate and sucrose tetraerucate are particularly preferred. These materials are available commercially as Ryoto Sugar Esters ex Mitsubishi Kasei Foods.
It is also advantageous if the ester groups of the fatty acid polyester are independently of one another attached to a fatty (C8 to C22 alkyl or alkenyl) chain or a short chain alkyl (C2 to C8) chain and in which the number ratio of C8 to C22 groups to C2 to C8 groups in the fatty acid polyester molecule ranges from 5:3 to 3:5, preferably from 2:1 to 1:2, more preferably about 1:1. The polyol used to prepare such a material is preferably a saccharide, most preferably glucose, with at least five of the hydroxyl groups being esterified. These products are in the main oils and are thus easy to formulate. Specific examples are glucose penta esters where about 50% by number of the ester groups are acetyl groups and about 50% by number of the ester groups are octanoyl, decanoyl or dodecanoyl groups respectively. The synthesis of this type of material is described in WO98/16538.
The fatty acid polyester can be prepared by a variety of methods well known to those skilled in the art. These methods include acylation of the cyclic polyol or reduced saccharide with an acid chloride; trans-esterification of the cyclic polyol or reduced saccharide fatty acid esters using a variety of catalysts; acylation of the cyclic polyol or reduced saccharide with an acid anhydride and acylation of the cyclic polyol or reduced saccharide with a fatty acid. Typical preparations of these materials are disclosed in U.S. Pat. No. 4,386,213 and AU 14416/88.
The total amount of fatty acid polyester in hair treatment compositions of the invention is generally from 0.001 to 10% by weight, preferably from 0.01 to 5%, more preferably from 0.01% to 3% by weight of the total hair treatment composition.
Compositions of this invention may contain any other ingredient normally used in hair treatment formulations. These other ingredients may include viscosity modifiers, preservatives, colouring agents, polyols such as glycerine and polypropylene glycol, chelating agents such as EDTA, antioxidants such as vitamin E acetate, fragrances, antimicrobials and sunscreens. Each of these ingredients will be present in an amount effective to accomplish its purpose. Generally these optional ingredients are included individually at a level of up to about 5% by weight of the total composition.
Preferably, compositions of this invention also contain adjuvants suitable for hair care. Generally such ingredients are included individually at a level of up to 2%, preferably up to 1%, by weight of the total composition.
Among suitable hair care adjuvants, are:
(i) natural hair root nutrients, such as amino acids and sugars. Examples of suitable amino acids include arginine, cysteine, glucamine, glutamic acid, isoleucine, leucine, methionine, serine and valine, and/or precursors and derivatives thereof. The amino acids may be added singly, in mixtures, or in the form of peptides, e.g. di- and tripeptides. The amino acids may also be added in the form of a protein hydrolysate, such as a keratin or collagen hydrolysate. Suitable sugars are glucose, dextrose and fructose. These may be added singly or in the form of, e.g. fruit extracts.
(ii) hair fibre benefit agents. Examples are:
ceramides, for moisturising the fibre and maintaining cuticle integrity. Ceramides are available by extraction from natural sources, or as synthetic ceramides and pseudoceramides. A preferred ceramide is Ceramide II, ex Quest. Mixtures of ceramides may also be suitable, such as Ceramides LS, ex Laboratoires Serobiologiques.
free fatty acids, for cuticle repair and damage prevention. Examples are branched chain fatty acids such as 18-methyleicosanoic acid and other homologues of this series, straight chain fatty acids such as stearic, myristic and palmitic acids, and unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid and arachidonic acid. A preferred fatty acid is oleic acid. The fatty acids may be added singly, as mixtures, or in the form of blends derived from extracts of, e.g. lanolin.
Mixtures of any of the above active ingredients may also be used.
The invention is further illustrated by way of the following non-limitative Examples, in which all percentages quoted are by weight based on total weight unless otherwise stated.

Unilever Home and Personal Care USA division of Conopco, Inc.


The invention relates to a non-dusting, homogeneous pigment preparation, comprising

The invention relates to a non-dusting homogeneous pigment preparation and to its use as a precursor for printing inks.
In industrial processes, pigments are seldom employed in the form of dry powders, since the latter produce dust, which leads to increased requirements in terms of workplace safety. In many cases, furthermore, when introducing powders into plastics, basecoat systems, etc., agglomeration of the pigment powder is observed. Homogeneous distribution of the pigment in the respective matrix is frequently difficult if not impossible to achieve.
Instead of the pigment powder, non-dusting pigment formulations are used. These formulations are:
free-flowing powders where pearl lustre pigments are coated with polymers, as described for example in DE-C-2603211,
pigmented free-flowing powders with a low moisture content, as known, for example, from DE-A-4139993,
pigmented powders having a higher moisture content, which owing to their flowable consistency are also frequently referred to as pastes, or
dry preparations as precursors for printing inks, as are known for example in EP 0 803 552.
Pastes, and dry preparations prepared from them, are a technical alternative to the dry or moistened powders provided they meet the following general conditions:
flowable consistency
minimal dilatancy
maximum pigment content
The components of the preparation/paste should be chosen so that the formulation is customized to suit the other components of the respective coating system as closely as possible and is readily homogeneously distributed following its introduction.
In addition to good compatibility with the other constituents of the coating system, pigment preparations are required to exhibit high stability; that is, they must not tend towards phase separation.
This requirement is particularly important in the case of pigment granules based on platelet-shaped pigments, since owing to their structure such pigments have a tendency to cake together on phase separation and are difficult to reagitate. Pigments based on platelet-shaped substrates give rise to handling problems insofar as, owing to the size and density of the pigments, they readily settle and then may cake together to form a very firm sediment cake. This cake is generally difficult to reagitate. This is particularly so in connection with the storage of varnishes, paints and printing inks and their processing.
Therefore, numerous methods have been developed, inter alia, in order to solve the problem of the incorporation and handling of platelet-shaped pigments in coating compositions. Reagitation can be facilitated by treating the coating compositions with additives which alternatively bring about controlled flocculation (house of cards effect), pseudoplastic and/or thixotropic behaviour, or steric and/or electrostatic repulsion of the pigments. However, these additives may have an adverse effect on the quality of the coating. In particular, the brightness in the case of effect pigments, and the uniformity of the coating, may be impaired.
In addition, homogeneous stable distribution of the redispersants in the pearl lustre pigment powder is difficult to achieve, and/or the redispersant loses some of its activity in the course of mixing.
The effect pigment formulations that have been developed to date for use in coating systems, with a pigment content of  greater than 30% by weight, frequently fail to go far enough towards meeting the requirements described, especially since they have a tendency towards agglomeration and shear thickening.
The object of the present invention was therefore to provide a pigment preparation, especially in the form of pastes and dry preparations, which can be used to very good effect in aqueous coating systems, possesses high stability, is readily redispersed, and at the same time features a high level of compatibility with the other components of the coating system. Furthermore, the pigment preparation of the invention ought also to be suitable for producing dry preparations in the form, for example, of pellets, granules, etc.
Surprisingly it has been found that this object can be achieved by the provision of the pigment preparation of the invention.
The invention therefore provides a non-dusting homogeneous pigment preparation which comprises
Depending on its moisture content, the preparation of the invention is a flowable paste or a moistened free-flowing powder. Both paste and powder are highly suited to the production of dry preparations, examples being pellets, granules and briquettes. The dry preparations produced lrom the pigment formulation of the invention are likewise provided by the invention.
The effect pigments used are preferably commercially customary metal-effect pigments, such as aluminium flakes, e.g. Stapa-Alupaste(copyright) or Standart from Eckart, Paliochrom(copyright) from BASF, platelet-shaped iron oxide, BiOCl, holographic pigments, and also pigments based on platelet-shaped, transparent or semi-transparent substrates of, for example, phyllosilicates, such as mica, synthetic mica, SiO2 flakes, TiO2 flakes, Al2O3 flakes, glass flakes, graphite flakes, talc, sericite, kaolin or other silicatic materials which are coated with coloured or colourless metal oxides, such as TiO2, titanium suboxides, titanium oxinitrides, Fe2O3, Fe3O 4, SnO2, Cr2O3, ZnO, CuO, TiO and other metal oxides, alone or in a mixture, in one uniform layer or in successive layers (multilayer pigments). Pearl lustre pigments are known, for example, from the German Patents and Patent Applications 14 67 468, 19 59 998, 20 09 566, 22 14 454, 22 15 191, 22 44 298, 23 13 331, 25 22 572, 31 37 808, 31 37 809, 31 51 343, 31 51 354, 31 51 355, 32 11 602 32 35 017 and P 38 42 330 and are obtainable commercially, for example under the brand name Iriodine(copyright) from Merck KGBA, Darmstadt, FRG. Particularly preferred pigment granules comprise TiO2/mica, Fe2O3/mica and/or TiO2/Fe2O3 mica pigments. The SiO2 flakes can be coated, for example, as described in WO 93/08237 (wet-chemical coating) or DE-A 196 14 637 (CVD process).
The pigment preparations of the invention can comprise one or more effect pigments. In many cases it is possible by using at least two different effect pigments to obtain special colour effects and lustre effects. Preferred pigment granules comprise one or more effect pigments based on mica and/or SiO2 flakes.
It is also possible to mix in conventional (organic or inorganic) colour pigments and also carbon black and/or TiO2.
The pigment formulation of the invention comprises preferably 50-95 t by weight of effect pigments, especially 60-80% by weight. Very particular preference is given to pigment granules having an effect pigment content of more than 50% by weight.
As a mandatory component the pigment preparation of the invention comprises a polyalkylene glycol and/or an appropriate derivative in amounts of from 0.5 to 60% by weight, preferably from 5 to 40% by weight and, in particular, from 10 to 30% by weight. All polyalkylene glycols or derivatives thereof that are known to the person skilled in the art can be used. Polyethylene glycol, polypropylene glycol and their esters and ethers are particularly suitable, as are described, for example, in xe2x80x9cEncyclopaedia of Polymer Science and Engineeringxe2x80x9d, a Wiley-Interscience Publication, John Wiley and Sons.
Furthermore, it is often advisable to mix in hydroxyl-rich resins, examples being cellulose products such as carboxycellulose and its ethers and esters, polyvinyl alcohol, polysaccharides and polyvinyl acetate, in amounts of from 0-50% by weight. All hydroxyl-rich resins known to the person skilled in the art are suitable, especially those specified in Karsten, Lackrohstofftabellen, 8th edition 1987.
As a further component the pigment formulation of the invention can comprise a redispersing auxiliary, preferably spherical particles, a polyacrylate or polymethacrylate, or fibriform particle having a fibre length of 0.1-20 xcexcm, in amounts of from 0 to 10% by weight, preferably from 0.05to 5% by weight and, in particular, from 0.01 to 3% by weight, based on the pigment.
The addition of a redispersing auxiliary in the form of bulky particles, such as fibres or spherical particles, for example, prevents the effect pigments treated in accordance with the process of the invention from lying on top of one another to a notable extent as a result of the steric repulsion and so exerting strong adhesion. The effects of this are that
1. the preparations of the invention are more stable,
2. owing to the introduction of the redispersing auxiliary into the varnish or paint system by way of the pigment preparation, the effect pigments undergo in some cases very much slower settling in varnish and paint systems, and
3. in all cases, the sediment is less hard, and no problems occur on reagitation of the sediment.
All organic and inorganic fibres that are known to the person skilled in the art and have a fibre length of 0.1-20 xcexcm can be used. Particularly suitable particles are all synthetic fibres made, for example, from polyethylene, polyacrylates, polypropylene, polyamides, cellulose fibres, inorganic fibres, and preferably silicone compounds, glass fibres and, in particular, the condensation products of modified isocyanates and mono- and diamines.
These condensation products, which are diurea derivatives and also amino ureas with urethane groups are known as thixotropic agents and, together with a binder, are added to paints and varnishes in order to improve the running properties and the brushability.
Redispersing auxiliaries which can be used are all diurea derivatives and urethane compounds known to the person skilled in the art, as are described, for example, in EP 0 198 519, in DE 18 05 693 and in Organic Coatings: Science and Technology, A. Heenriga, P. J. G. von Hemsbergen, pp. 201-222, N.Y. 1983.
Suitable spherical materials are, in particular, hollow glass, wax or polymer beads made from vinyl resins, nylon, silicon, epoxy resins, olefin resins or polystyrenes, and inorganic materials, such as TiO2, SiO2 or ZrO2, for example. Preference is given to the use of hollow beads, and also solid beads, having a particle size of from 0.05 to 150 xcexcm. With particular preference, hollow glass, wax or polymer beads are employed in the pigment granules of the invention.
Spherical particles based on SiO2 in a particle range of 3-10 m are known, for example, as materials for high-performance liquid chromatography and are marketed, for example, as LiChrospher(copyright) by Merck KGaA, Darmstadt, FRG. Such materials are preferably employed in monodisperse form, that is, with a substantially uniform particle size. Monodisperse spherical particles of this type based on SiO2, TiO2 and ZrO2 are known. Monodisperse SiO2, for example, can be prepared in accordance with DE 36 16 133. Hollow glass beads are marketed, for example, under the trade name Q-CEL by PQ Corporation, USA or Scotchlite by 3M, Frankfurt, FRG.
In addition, the preparation may comprise surface-active substances, such as alkylsilanes, which may also contain a further functional group, unsaturated or saturated fatty acids, or fluorosurfactants. Particular preference is given to the use of silane compounds of the formula (CnH2n+1) Si (OCmH2m+1)3, in which n is 1-30 and m is 1-10, as surface-active substances. Examples of suitable silane compounds are n-hexyldecyltriethoxysilane and n-octyldecyltriethoxylsilane (Si 116 and Si 118, respectively, from Degussa AG, Frankfurt, FRG), and also the corresponding fluoroalkylsilanes.
Further surface-active substances which can be employed are the saturated and unsaturated fatty acids, such as caproic, caprylic, capric, lauric, myristic, palmitic, stearic, oleic and linoleic acid, and also mixtures of fatty acids.
In addition to the silane, the pigment preparation preferably also comprises a surfacrant or a fatty acid. The surface-active reagent may also be a mixture of silane, fatty acids and/or surfactants. The pigment preparation can comprise from 0.1 to 5% by weight, preferably from 0.2 to 3% by weight and, in particular, from 0.5 to 2% by weight of surface-active substances, based on the pigment.
The pigment preparation of the invention may additionally comprise from 0 to 40% by weight of water or an organic solvent or solvent mixture, preferably from 5 to 35% by weight and, in particular, from 10 to 30% by weight.
The solvent component in the pigment preparation of the invention must be expertly tailored to the polyalkylene glycol that is used. For the preparation it is possible to employ all organic solvents, especially those which are miscible with water. Suitable solvents are, for example, aromatic solvents, such as toluenes, petroleum spirits, mineral oils, hydrocarbons, esters, long-chain amines, vegetable oils, monohydric aliphatic alcohols, such as those having 2 to 4 carbon atoms, examples being ethanol, butanol and isopropanol, or ketones, such as acetone or methyl ethyl ketone, or glycol ethers, such as propylene glycol monoethyl ether, or diols, such as ethylene glycol and propylene glycol or polyetherdiols, aliphatic triols and tetrols with 2 to 6 carbon atoms, such as trimethylolethane, trimethylolpropane, glycerol, 1,2,4-butanetriol, 1,2,6-hexanetriol and pentaerythritol, and also all other solvents from other classes of compound, and/or mixtures of the abovementioned solvents. Preference is given to the use of those solvents listed in Karsten, Lackrohstofftabellen, 8th edition, 1987.
The pigment preparation of the invention is produced by adding the polyalkylene glycol and/or the polyalkylene glycol derivative, water if required, the redispersing auxiliary, and any further additives simultaneously or in succession to the effect pigment or effect pigment mixture and gently homogenizing this mixture in a mixer. The mixers are not critical, but dispermats, granulating mixers and blade mixers.
Preferably, the pigment is introduced initially and is first pasted up, while stirring, with the solvent containing the polyalkylene glycol and possibly at this stage the redispersant; next, if desired, a further solution consisting of solvent, additives and the redispersing auxiliary is added. It desired, a first drying stage can be carried out even at this point, in which case the drying temperature can be between 80 and 150xc2x0C.
During its preparation or after it has been prepared, further customary additives can be added to the pigment preparation of the invention, examples being pH regulators, defoamers, wetting agents, anti-settling agents, levelling agents, siccatives and thixotropic agents. These are auxiliaries customary in the coatings industry, which may be present in the pigment preparation of the invention in an amount from 0 to 10% by weight.
The resultant pigment preparation of the invention is a homogeneous powder or readily flowable paste having a relatively high effect pigment content. Because of the particularly high level of compatibility of the hydroxy resin, the pigment preparation of the invention is likewise thoroughly compatible with customary commercial systems.
Further distinguishing features of the preparation are its freedom from dust, ready dispersibility and redispersibility, high storage stability and good processing properties, and it is therefore markedly superior to conventional pigment preparations.
The flowable pigment preparation is very well suited to the filling of tubes, and for extrusion. In order to produce dry preparations, the pigment granules of the invention are extruded or compressed into a compact particulate form by other means known to the person skilled in the artxe2x80x94for example, by tableting, briqueting, pelletizing, granulating, spray-granulating or extrusionxe2x80x94and may then be dried.
The processes referred to are known to the person skilled in the art and are described in xe2x80x9cSize Enlargement by Agglomerationxe2x80x9d, Wolfgang Pietsch, John Wiley and Sons, Chichester, N.Y., Brisbane, Toronto, Singapore 1991.
When the pigment preparation or paste is pressed through a perforated plate, which is done either batchwise by means of pistons or continuously through an extruder, particles in sausage form are produced. By appropriately adjusting the viscosity of the preparation it can be ensured that the length of the particles is regulated automatically as a result of breaking off or tearing off on emergence from the perforated plate. The separation of the paste extrudates emerging from the perforated plate, to form particles, can alternatively be done by known mechanical means, for example by rotating separation blades. Pelletization or granulation takes place in a known manner on pelletizing plates or in granulating vessels and generally results in spherical particles of the preparation.
The preparation of pigment granules by way of plates or drums may be advantageous in certain cases in order to ensure that only a minimum of auxiliary solvent and/or water is used. The pigment preparations used as starting material for this purpose are generally moistened powders, which in some cases may already be in granulated form, and with the further process step are used merely like the desired defined particles.
The particles produced firstly by pressing through a perforated plate can subsequently be shaped further by pelletization or granulation. Tableting or briqueting takes place by pressing the paste in appropriate moulds.
The process of drying the particles produced by compacting takes place generally at temperatures from 20 to 150xc2x0 C., lasts for between 0.5 and 4 h and can be carried out, if desired, under reduced pressure. First of all, the dry preparation is classified or comminuted if desired. The granules obtained in this way, for example, are likewise non-dusting and have particle sizes in the range 0.1-150 mm, preferably 0.1-20 mm and, in particular, 0.1-2 mm. The storage and transportation of the dry preparations are not subject to any great restriction and are therefore highly unproblematic. The dry preparations possess the further advantage that they carry little or no liquid and therefore possess increased stability and compatibility.
The dry preparation can also be prepared in the absence of water and/or solvents by processing the resin and other components with the pigment at increased temperature to form a flowable or free-flowing melt and producing granules from this melt by forming drops, by centrifugation or by the use of granulating plates or drums.
The pigment granules can also be admixed with substances which assist or accelerate the breakdown and dissolution of the pigment granules, examples being bulky spherical particles, such as hollow beads, or half beads, or substances which dissolve very rapidly in the application medium, or swell and in that way xe2x80x9cburstxe2x80x9d the granules.
These dry preparations can be incorporated into all of the binders known to the person skilled in the art for varnishes, paints and printing inks, especially aqueous solvent-free (UV) and also solvent-based systems.
Owing to the good compatibility of the polyalkylene glycols and derivatives thereof, suitable binder resins are those which are commonly added to paints and varnishes and are listed, for example, in Karsten, Lackrohstofftabellen, 8th edition, 1987. Suitable binders are all of those binders or binder mixtures that are customarily used for printing inks, examples being those based on cellulose, polyacrylate, polymethacrylate, alkyd, polyester, polyphenol, urea, melamine, polyterpene, polyvinyl, polyvinyl chloride and polyvinylpyrrolidone resins, polystyrenes, polyolefins, indene-coumarone, hydrocarbon, ketone, aldehyde and aromatic-formaldehyde resins, carbamic acid resins, sulfonamide resins and epoxy resins, polyurethanes and/or natural oils or derivatives of the substances mentioned. The effect pigment preparation of the invention has been found to exhibit particularly good redispersibility when cellulose and/or cellulose compounds are employed as binders.
The integration of a redispersing aid ensures that, even in the finished varnish and paint systems, the pigment granules of the invention are readily reagitatable and require no further improvement by the end formulator.
The improved deagglomeration of the dry preparations incorporated into a binder, such as into a printing ink, for example, is evident even with small amounts of spherical particles in the pigment granules. For instance, even when using granules having a spherical particle content of 0.5% by weight, based on the dry pigment, the dissolution rate is markedly increased and the printing ink becomes stable (viscosity/hue) more quickly.
As a paste or as dry granules, the preparation of the invention can be used for a variety of applications. It is preferably employed in coating systems from the sectors of printing, especially offset printing, flexographic printing and intaglio printing, print varnishing and screen printing. With particular preference, the granules are applied, as a precursor for coating compositions, to any desired substrate materials, examples being metals such as iron, steel, aluminium, copper, bronze, brass and also metal foils, and metal-clad surfaces of glass, ceramic and concrete, and on wood, such as furniture, for example, clay, textile, paper, packaging materials, for example plastic containers, films or card, or on other materials for decorative and/or protective purposes.
The invention therefore also provides for the use of the pigment preparation, as a paste or as a dry preparation, in formulations such as paints, varnishes, printing inks and plastics.

Abstract: xe2x89xa740% by weight of one or more effect pigments,

Abstract: 0.5-60% by weight of a polyalkylene glycol and/or one or more polyalkylene glycol derivatives,

Abstract: 0-10% by weight of a redispersing auxiliary,

Abstract: 0-40% by weight of water or an organic solvent or solvent mixture,

Abstract: 0-40% by weight of at least one further hydroxyl-rich resin,

Merck Patent Gesellschaft mit beschrxc3xa4nkter Haftung


The invention relates to a road surface marking tape intended for temporary use and being of the kind that includes a base layer of non-cured or non-vulcanized soft elastomeric material, and reinforcing material embedded in the base layer. The reinforcing material is comprised of short fibers of non-metallic material distributed generally uniformly in the base layer in an amount corresponding to 5-50%, preferably 10-20% of the weight of the base layer. The reinforcing material is preferably comprised of fibers of fabric, plastic or carbon with lengths generally between 0.5 and 5 mm, preferably between 1 and 3 mm. The elastomeric material is usually a rubber of the acrylnitrile-butadiene type. The invention also relates to a method of temporarily marking the surface of a road or highway with the aid of the inventive tape, wherein the tape is applied to said surface in the form of an elongated web taken from a tape reel with the aid of an appropriate mechanical tape-laying device, and removed when the traffic markings are no longer required, by freezing the tape to a brittle state and disintegrating the tape to a powder form and collecting said powder mechanically. Freezing, disintegration and collection of the tape material can be effected mechanically in one single step. The tape is conveniently disintegrated by brushing with a rotating steel brush or the like, and the resultant tape scrap is removed by suction.

The present invention relates to road surface marking tape for temporary use in marking out temporary traffic diversions and comprising a base layer of nonvulcanized or non-cured soft elastomeric material and a reinforcing material embedded in the base layer. The present invention also relates to a method marking road surfaces with the aid of such tape.
It is known to use to mark the surfaces of roads, highways, etc., with a foil material which is based on a polymeric base layer, for instance a resin, thermoplastic, thermoelastomeric or rubber material, that includes a heavily light-reflecting layer which includes pigments, colorants, and/or glass beads embedded either in the base layer or in an upper layer adjacent said base layer, or in both of said layers. Such materials are described, for instance, in U.S. Pat. Nos. 2,440,584, 3,764,455, 3,915,771, 4,117,192, 4,248,932, 4,282,281 and 4,299,874, and also in EP-A 614503 and SE-B 458215. A common feature of all of the known materials described in said publications is that they are intended for permanent use and are thus designed and adapted for such use. The most important properties required of such road surface marking foils lie in their high mechanical strength, i.e. high wear strength, high abrasive resistance with respect to their reflective layers, a long useful life, etc. The base layer has therefore been designed to meet these requirements. As a result such road surface marking foils are relatively rigid and will have certain drawbacks with respect to compatibility and conformity to the state of the road surface on which they are laid, and also with respect to their ability to effectively adhere to and lie in tight abutment with said surface, even when a soft polymeric material is used. Consequently, it is preferable in the majority of cases, at least in normal outdoor temperatures in a temperate climate, to apply a primary layer consisting of a rubber solution or the like prior to applying the foil to the road surface. Such road surface marking materials are unsuitable for applications where only a temporary marking is required, for instance over a time period of up to 10-12 months, for a number of reasons. Such materials are not easily removed without leaving any trace, due to the use of the primer. The primer is absolutely necessary in achieving effective adhesion, since the marking material is relatively thick and thus also relatively stiff and difficult to xe2x80x9cmoldxe2x80x9d to the irregularities of the road surface, as inferred above. These materials are also highly expensive and are discarded as waste when their use is fulfilled. The waste material is also difficult to handle in a manner that is environmentally acceptable.
There is thus a need to be able to use foil-type road-surface marking material, hereinafter called road marking tape, also for temporary purposes instead of needing to use less effective and less traffic-safe markings with loose or firmly mounted cones or other similar xe2x80x9cmechanicalxe2x80x9d solutions, or by painting directly on the road surface, such painted markings being difficult to erase when no longer required. Although various types of temporary road-marking materials based on metal foil, for instance aluminium foil, are now commercially available, these materials are relatively expensive and do not have sufficient strength and wear resistance. The removal of such materials from a road surface also presents serious problems when said materials have been applied to said surface with the aid of a strong adhesive.
Road-surface marking tape of the kind defined in the introduction and primarily intended for temporary use in diverting road traffic is described in EP-A 0304405. The tape contains a very soft and formable non-cured elastomer based on acrylnitrile-butadiene which forms a base layer having a thickness of about 0.5 mm. This layer is much thinner than corresponding layers of earlier used permanent tapes and is therefore considered to have properties which enable the tape to be laid directly on the road surface with good adhesion and conformity with respect to irregularities in the road surface. However, the preferred embodiments include an adhesive layer on the undersurface of the tape for effective adhesion of the tape to said surface, such adhesive layers probably being always used in practice. The base layer contains both pigments and glass beads which provide the tape with the desired optical reflective properties. The base layer is reinforced with a strengthening layer which is embedded at least partially into the elastomeric base layer, in order to facilitate handling of the tape in practice on the one hand and, on the other hand, to impart to the tape the mechanical strength properties required when laying-out the tape, such as high tensile strength and appropriate ultimate tensile strength so that tape can be torn away from said road surface when necessary. The reinforcing layer is said to have the form of a plastic, metal or fabric net, preferably with square or rectangular meshes. According to the main Claim of said patent publication, it is necessary for the reinforcing layer to be embedded at least partially in the base layer.
Although the reinforcing layer solves certain strength problems, primarily with respect to removing the tapexe2x80x94which is done manuallyxe2x80x94by tearing up the tape piece-by-piece until all of the tape has been removed, it creates other problems relating to the ability to mold the base layer to irregularities in the road surface and therewith enable the tape to be placed in tight abutment with said surface for effective and durable adhesion thereto. Thus, although without being specifically mentioned, the reinforcement has on the base layer a mechanically stiffening effect that reduces the mouldability or shaping ability of the tape and therewith deleteriously affects the conditions required to achieve effective adhesion and sealing of the tape to said road surface. The reinforcement also means that the tape cannot be readily handled after its removal and presents a problem with regard to carrying the used tape away as scrap and also with regard to recycling or reusing the material. Because the reinforcing net reduces the pliability of the road marking tape for temporary use, it is often preferred to use a primary coating to facilitate adhesion of the tape. This solution, however, is encumbered with other drawbacks, such as extra costs entailed by material, solvent, manufacture and placement, additional work involved when laying-out and removing the tape, and increased environmental problems due to the requirement of a solvent.
The object of the present invention is to provide a road surface marking tape for temporary use which is based on a base layer of non-cured or non-vulcanized soft elastomeric material and a reinforcing material which imparts to the base layer, and therewith to the tape as a whole, a firmness and tensile strength sufficient to facilitate handling of the tape, and to a method of laying-out and removing such tape while avoiding the drawbacks described in the introduction. To this end, the inventive marking tape is characterised by the characteristic features set forth in respective product Claims, while the inventive method is characterised by the method steps set forth in respective method Claims.
The inventive marking tape thus includes a base layer of soft, non-vulcanized or non-cured elastomeric material, and a reinforcing material embedded therein, said reinforcing material comprising short non-metallic fibres distributed essentially uniformly in the base layer.
The short fibres are present in an amount corresponding to 5-50% of the weight of the base layer. By xe2x80x9cshortxe2x80x9d fibres is meant in this case primarily the opposite of xe2x80x9clongxe2x80x9d fibres and suitably a fibre length that corresponds to the thickness of the base layer or shorter than said thickness. With respect to the amount of fibres present in the reinforcing layer, the lower limit of 5% represents a limit at which the base layer, and therewith the tape as a whole, will have insufficient tensile strength and/or an excessively high rupture strain and thus having the behaviour of a viscous chewing gum-like material that is difficult to stretch and almost impossible to handle when laying-out the tape. The upper limit of 50% with respect to fibre content provides a base layer which can be handled relatively well and which is acceptably pliable at least at such high outdoor temperatures as those experienced in tropical regions. A fibre content above this upper limit, however, will greatly impair the suppleness, i.e. shapability, of the tape such that the tape can no longer be used as a road surface marking tape. The reinforcing material will preferably comprise fibres that have lengths generally between 0.5 and 5 mm, preferably between 1 and 3 mm, which has been found to provide an optimal compromise between different tape properties. The material will preferably comprise textile fibres, plastic fibres or carbon fibres. Textile fibres are preferred in most cases. A tape that has optimum strength properties when used in normal outdoor temperatures in a temperate climate is obtained when the fibres are present in an amount corresponding to 10-20% of the weight of the base layer.
The elastomeric material is suitably a non-vulcanized synthetic rubber of the acrylnitrile-butadiene type.
According to the inventive method of providing road surfaces with a temporary marking or signalising system with the aid of an inventive tape, the tape is unwound continuously from a tape roll with the aid of an appropriate mechanical tape-laying device. When the tape is to be removed at the end of said temporary period, the tape is frozen to a brittle state and disintegrated mechanically to powder form or to fragmentary state, and then swept up or removed in some other way. The steps of freezing the tape so that it disintegrates and the step of removing the disintegrated powdery material are both effected mechanically, preferably essentially at one and the same time in a single step. The frozen tape is disintegrated with the aid of a rotary steel brush or some corresponding device, and the powder, or fragments, are removed by suction.

Road surface marking tape for temporary use and a method of such use